The present invention basically relates to methods and equipment for preventing separation in bulk materials, which contains material of different particle sizes.
The invention has come into being for solving the problem with the separation occurring in ballast material included in the asphalt composition ordinarily used for metalling roads, streets and the like. It is, however, not limited to this particular application but can be utilized in many different fields, e.g. with concrete, manuring agents and the like, in which particles or ingredients are included that have varying sizes.
Very often, the metalling on streets and roads has an uneven quality due to the ballast material in the asphalt composition having separated during the different steps in transport, when the composition is transferred first from the asphalt works to an intermediate storage sealer and then from this to the transport vehicle and from there to the layer and at last out on the roadway. In each step, each material size in the ballast material strives to collect at the sloping surfaces automatically formed when the asphalt composition is tipped.
The uneven structure of the laid asphalt composition results in the risk of traffic accidents increasing since certain areas get poor water runoff, the risk of water planing then increasing, and wear will be uneven so that the roadway can be wavy and repair patching must take place.
For several reasons, it would therefore be a saving if the quality on the laid asphalt composition could be made better than what the case is today. The roadway could be made more safe for traffic with less risk of different types of skidding accidents as well as other types of accident, and maintenance could be reduced by avoiding patching and repairing individual places. Instead, larger road sections could be renovated at greater intervals than what is the case today, which is something which could save costs in the order of millions every year in roadway maintenance.